Working to protect against the dangers of dengue

  “A small, modest investment from the US government could truly transform the lives of people around the world and make a serious public health impact,” Rachel Cohen from the Drugs for Neglected Diseases initiative said yesterday at a congressional briefing focused on neglected tropical diseases (NTDs). NTDs are a group of 17 diseases that infect more than one billion people around the world, most of whom live on less than $1.25 per day. The briefing focused on how the US government has played a significant role in combatting NTDs globally through programs like those at the US Agency for International Development (USAID), which has helped deliver more than half a billion treatments in six years to more than 250 million people. At the same time, Cohen and other panelists stressed that significant changes are needed to make US NTD programs even more successful. For instance, several speakers argued that while USAID’s NTD program has been remarkable in its efforts to provide NTD patients with access to existing therapies, the agency must expand the program to include funding for research into new NTD drugs, vaccines, and diagnostics. The fact that USAID does not currently support NTD product development “is a serious gap in USAID’s efforts against NTDs, as most NTDs do not have adequate prevention, diagnostic, or treatment options,” moderator Kaitlin Christenson, GHTC’s coalition director, pointed out. She added that “many existing NTD drugs are toxic, expensive, and difficult to administer in resource-poor settings.” Christenson and other panelists added that congressional support is critical for USAID to expand its mandate into NTD research and product development. Panelists at a Congressional briefing on Monday discuss the US response to neglected tropical diseases. From left: Kaitlin Christenson, Brian D'Cruz, Rachel Cohen, and Larry Buxbaum. Credit: Research!America Panelists also highlighted that USAID’s program—which currently addresses only seven NTDs—should expand to include research and control efforts for all 17 diseases. Dr. Brian D’Cruz, an emergency physician who has served with Médecins Sans Frontières (MSF), discussed his experience providing treatment for sleeping sickness in the Central African Republic and Democratic Republic of the Congo to illustrate the need for expanded US support. D’Cruz told the story of Natasha, a 12-year-old girl in the Congo who died of sleeping sickness before his MSF team could provide adequate diagnosis and treatment. He added that MSF physicians are hindered in their efforts to treat patients like Natasha by cumbersome diagnostics and outdated, lengthy treatment regimens. Dr. Larry Buxbaum with the Philadelphia Research and Educational Foundation also highlighted that many NTDs, such as Chagas, are increasingly affecting populations in the United States. “Climate change is moving many tropical diseases north,” he said, adding “So while research is needed to help people with NTDs in Africa and South America, this research will be useful right here in the US as well.” D’Cruz also said that he has treated patients with Chagas disease in his capacity as a physician in Northern Virginia: “These NTDs exist just a few metro stops away.” Finally, all the panelists urged US policymakers to become increasingly involved in an ongoing global discussion about how to redefine NTD research and product development efforts. All three of these changes—investing in NTD product development, expanded support for all 17 NTDs, and engaging in global discussions about NTD research—will help ensure that the US makes the greatest impact possible against NTDs worldwide. “We need breakthrough, completely modern therapies and diagnostics for these diseases,” Cohen said, adding, “They are literally in the pipeline. US support could help us get closer and closer to elimination.”

In this guest post, Jessie L. Dyer, MSPH, in the Centers for Disease Control and Prevention’s (CDC) Rabies Program, writes about the agency’s work with partners in Haiti to fight the disease. She focuses here on the implementation of a low-cost rabies diagnostic test that could make better use of scarce resources and save lives in this developing Caribbean nation. This is the third in a four-part series by experts from CDC’s National Center for Emerging and Zoonotic Infectious Diseases. Often the shred of truth behind legends, rabies is an ancient disease that has inspired countless stories and cautionary tales throughout the world. The Caribbean island nation of Haiti is no different. Historical records warn of rabid man-eating dogs brought to the island by French colonist as early as 1791. Fast-forward more than 200 years, and you’ll find that rabies is now endemic in Haiti—meaning it is commonly found in dogs, mongooses, and possibly bats. Haiti also reports the highest number of suspected human rabies cases of all Latin American and Caribbean countries. Children are the most vulnerable age group for rabies exposure throughout the world. Credit: Michael Niezgoda, CDC. For the past 2 years, while working with the CDC’s Rabies Program in Haiti, I’ve heard many personal stories about “mad” dogs and learned first-hand about the large-scale collaborative effort that is needed to prevent and control rabies. Rabies is a terrifying disease, and once symptoms present, death is inevitable. Yet, most people do not know how to protect themselves. Without the appropriate post-exposure prophylaxis (PEP) after a suspected rabies exposure (usually a dog bite), rabies is almost always fatal.PEP consists of: Wound care (washing with soap) Administration of rabies immune globulin (antibodies that protect you until your body can produce its own antibodies against the rabies virus) Multiple doses of the rabies vaccine (given in the arm). Proper application of PEP can prevent the onset of rabies and death. CDC is one of many partners collaborating with the Haitian government to develop and implement a One Health approach to rabies prevention and control—an approach that encourages physicians, veterinarians, community workers, laboratory professionals, and public health and agriculture officials to work together to prevent and control this horrifying disease. Because rabies is a zoonotic disease, a disease spread between animals and humans, partnerships between human and animal health agencies are vital for successful implementation. For example, we work with Haiti’s Ministry of Public Health and Population (for human rabies prevention) and the Ministry of Agriculture, Natural Resources, and Rural Development (for animal rabies prevention and laboratory diagnostics). Our goal is to cut the incidence of human and canine rabies cases in half by 2015. We know we cannot do it alone, and that it will require efforts in many different areas, including laboratory diagnostics, surveillance, and community outreach. A crucial part of our efforts in Haiti is a push to expand laboratory capacity to quickly and accurately diagnose rabies. One promising new tool is the direct rapid immunohistochemistry test (DRIT), a low-cost test developed at CDC that can be used for initial diagnosis of rabies. The DRIT requires a light microscope, which is far less expensive than the fluorescence microscopes needed to perform the current world standard for rabies laboratory diagnoses—the direct fluorescent antibody test. Research has also shown that the DRIT has a higher specificity for the rabies virus than the test routinely used in Haiti—the Sellers staining method—which was developed in the 1920s and cannot confirm that the resulting stained inclusion is, for sure, the rabies virus (for example, it also stains inclusions caused by the canine distemper virus). Another benefit of accurate diagnostics is that it will strengthen rabies surveillance, which is a critical component for the control and elimination of canine rabies in Haiti. Our hope is that one day, through improved laboratory diagnostics, enhanced surveillance, and growing partnerships, we will better understand the true impact of this tragic and deadly disease in Haiti. The enormous potential of the DRIT gives hope for rabies prevention and control programs in resource-scarce countries such as Haiti.